Some babies are mellow, others are high-strung. And some babies seem prone to anger. Do these early behavioral differences tell us which kids will become defiant and aggressive?

It might seem obvious that an angry baby will become an angry, aggressive child. But when it comes to aggression, your baby’s moods may be less important than the way his autonomic nervous system responds to stimulation and stress. In an interesting new study, the babies who were the least responsive were the most likely to develop aggressive behavior problems as toddlers. Whether the babies were perceived as hot-tempered had nothing to do with it.

To understand, picture this: A 10-month old baby is strapped into a car seat with an unfamiliar adult nearby. His mother is watching him from another room, but he doesn’t know it. All he knows is that a strange, mechanical robot toy is approaching him from about 5 feet away. The robot makes noise and moves its arms, and doesn’t stop its approach until it’s just 6 inches away.

It’s designed to be scary, and it was. When Erika Baker and her colleagues at Cardiff University performed this test on 100 babies, they were careful to allow mothers to enter the room if, during the experiment, the babies seemed too distressed. Twelve of the mothers did that, and 44 of the babies cried at some point during the weird encounter.

But the reactions of special interest were autonomic. How did the experience affect the babies’ autonomic nervous system, the system that regulates mostly involuntary body functions like heart rate, digestion, and perspiration?

In general, our autonomic nervous system kicks into high gear when we encounter something exciting, good or bad: The heart beats faster, the breath quickens, our pupils dilate, and we break out into a sweat. But the level of arousal varies from person to person. Some people, “high arousal” people, are highly stimulated by relatively small things. Others – the “low arousal” people – are far less sensitive. An experience that triggers physiological changes in the average person might barely register for someone with low arousal.

So Baker’s team monitored the babies’ arousal levels by measuring “skin conductance activity,” i.e., changes in perspiration. Each baby had small electrodes taped to his feet, permitting the researchers to track perspiration before, during, and after the robot experience. In addition, the researchers questioned mothers about their babies’ behavior at home, and they asked mothers about their own behavior and feelings.

Two years later, the researchers were able to track down 70 of the families who had participated in the first phase of the study. Now they asked the parents to evaluate their children’s behavior using the Child Behavior Checklist, a standard developmental questionnaire.

The data were in. What were the results?

Baby temperament – as reported by mothers – was linked how much fear a baby showed during the robot encounter. But it wasn’t correlated with autonomic nervous system arousal. And it wasn’t correlated with the development of aggressive behavior problems. A mother’s perceptions of baby anger did not predict antisocial aggression at age 3.

The only measure that did predict future behavior problems was skin conductance reactivity – sweaty baby feet before and during the scary robot encounter. The babies who perspired less had a moderately increased risk of becoming aggressive toddlers.

As always, we have to be cautious about interpreting the results. For instance, it’s always hard to establish the absence of an effect (“mother’s perceptions of infant temperament not predictive”) with a small sample. And what about the people who declined to participate? Though you might argue the robot was no more distressing than many of the strangers that babies meet in real life, I don’t think I’d volunteer for a study like this. If highly sensitive or “high arousal” parents were more likely to opt out, that might have influenced the results.

Still, it’s hard to guess how such parents might have changed the outcome. And while this study doesn’t prove that parent ratings of baby temperament are unrelated to the development of aggression, it suggests that the effect – if it exists – is small. Moreover, the main positive finding of this study is consistent with other research:

In previous studies of children and adults, low autonomic arousal – as measured by skin conductance reactivity – has been linked with aggressive behavior problems.

Why might that be? There are theory popular theories.

In one account, people with low arousal find it harder to pay attention to ordinary things, which gets them into trouble. Another theory suggests that people with low arousal are more fearless, and, therefore, less constrained by the prospect of punishment or other negative consequences of aggression. A third is the well-known “thrill-seeking” or “sensation seeking” explanation. It supposes that low arousal motivates people to engage in a kind of self-therapy, boosting arousal levels by seeking out extra stimulation – some of which may involve aggression.

The theories aren’t mutually exclusive, and in fact they all offer hope for concerned parents. They suggest we can help low arousal children avoid aggressive behavior problems by applying some common sense. Does your kid have attention problems? Help him develop stronger self-regulation skills. Is he unfazed by punishment? Try focusing on the rewards of good behavior and the development of empathic, moral reasoning. Is he motivated to seek out thrills? Give him lots of positive opportunities to excite his senses and experience awe.

It’s not a recipe for perfection. Some kids present really difficult challenges. But understanding low arousal may help us focus on what these kids need the most.

image of Hulk by aut_toknow/photobucketimage of baby foot by Kopfjäger /wikimedia commons.image of kids at beach by Masahiro-Hayata / wikimedia commons

17 Responses to Can you tell if a baby is going to become an aggressive kid?

Thank you for posting this I have been having a lot of trouble punishing my 2 year old. She laughs when I spank her and she doesn’t quite understand the whole time out process. I’m going to try rewarding her good behavior and read the tips you gave in the link. One thing that still concerns me though is she has always hit herself when she gets frustrated or mad could that be a sign that she is going to have further behavioral problems as she gets older? This is something I have worried about since she started doing it around 9 months.

Yes, Milania’s Mommy, that is something to be concerned about — that she hits herself. It’s one of those behaviors that pediatricians want you to report. So ask your doctor for advice, and *don’t* get all worried and upset about it in the meantime. The reason child development experts tell us about these warning signs is so families can learn what steps to take to prevent future problems. I’d also skip the spanking and try other methods.

Good luck!

gentle mammasays:

April 27, 2013 at 9:12 pm

Milanias mommy maybe you shouldn’t spank your child. Your just teaching her that hitting is ok! Gentle redirection does work.

Amandasays:

April 27, 2013 at 9:35 pm

Actually, “gentle mama” Redirection NEVER worked for my 4 year old. and Redirection does NOT teach children to deal with their feelings, it just teaches them to distract themselves from Negative feelings and pretend they aren’t there.Also, all children are different and respond to different types of punishment better than others. Milania’s mommy, try putting her in a high chair for time out, hopefully, she will soon get it. Also if she is throwing violent tantrums, try holding her on your lap, facing away from you, and hold her arms across her chest gently,it worked for my oldest when he did that. i’ve had to do those things with my 13 month old already,and with my oldest when he was younger, and it works (for my sons anyways, all kids are different).

Jennasays:

April 27, 2013 at 11:08 pm

Maybe we should not judge others in the way they choose to raise, discipline, and educate their children. Let us just raise our own children as we sit fit and allow others to do the same.

Kristiesays:

April 28, 2013 at 3:29 am

I’m not sure I completely buy into this yet. There are to many variables in a two year period that could happen to affect the way a child acts under stress. To say that foot perspiration is an indicator of violent tendencies is a little far fetched for me to grasp ahold of. I certainly would but my LOs under in-needed stress to find out if they have a predisposition to violence. Learning to control your emotions and learning how to react to situations is a life long process, and any evironmental, physical, mental stimuli etc can change that. I have my child in church every Sunday, live out in the country, don’t let her watch violent tv programming and actively teach her what is acceptable behavior and what is not. I have rules that she needs to follow. All of this and more can affect a child’s tendency to violence. Not to mention mothers perception of the child. Every mother is going to see their child as the best in the world. So the surveys are going to be a little off there as well. So.. My opinion… There are to many variables to low autonomic response is an indicator that a child is going to be a more violent toddler.

Marie Coesays:

April 28, 2013 at 4:52 am

Redirection might work on some kids, never worked on my older boy. I think there are some cases where spanking is necessary, like when the child is putting themselves in a dangerous situation. IE, running into the road, aggrivating the animals ect. I had to do time out in the bedroom. Sorry in the corner he didn’t get the memo, in his room by himself yep he got the message. I think the ones who get themselves into trouble are the kids with no rules and no consequences. In other words people are letting them get away with stuff. Redirection is fine for a baby who forgets what he was getting into. Some older kids don’t forget they just keep goign after what they want unless there is a consequence

I actually don’t spank my daughter very often maybe 3 times total since she has been alive, I have only done after I put her in time out and she just refused to listen. My daughter isn’t even 2 she is 23 months she will be 2 in 2 weeks. So I know she doesn’t completely understand the concept of punishment yet. I don’t plan on spanking her all the time as a punishment but I felt at those times it was absolutely necessary. But anyway I’m going to have this discussion with her doctor, and in the future I will remember not to post about it on babycenter because other moms are going to judge me for parenting MY child.

Megglessays:

April 28, 2013 at 8:12 am

I’ve see some of this in my own kids. My first daughter is very sensitive (7), and looking back was easily aroused as a baby–excitable. She finds aggression very disturbing. It really impacts her. She has also been very susceptible to remorse. All I have to do is look at her cross-eyed and she’s usually contrite. She requires a lot of emotional reassurance. My second daughter couldn’t be more different. As a baby nothing seemed to faze her. Last year when she was 2 I had to discipline her over and over by sending her to the time-out spot. She is stubborn and I had to stand my ground. She is more aggressive than her big sister. Just recently she has started to express more remorse, and honestly I’m relieved! We’ll have to see how daughter number three is with these issues, but I think she’ll be somewhere in between the two.

As an emotionally sensitive person, I think sensitives find aggression and violence more disturbing than the average individual. This would definitely lead to a sensitive being less aggressive because they would want to avoid that disturbing feeling. Someone who wouldn’t feel the emotional impact of violence as much would be more likely to be aggressive.

Christine Hebertsays:

April 28, 2013 at 8:26 am

until I saw the bank draft saying $4410, I be certain that my friend was like actually earning money part-time on their laptop.. there neighbour had bean doing this for only 6 months and by now repayed the mortgage on their apartment and bourt a new Citroën DS. read more at, KEP2.COM

@ Milania’s Mommy: It sounds to me like you are doing what good parents do — paying attention to what’s not working, looking for new solutions, and getting your child screened for possible problems. So again, I don’t think you should worry. An expert might decide your child’s behavior is developmentally mainstream, or he might decide that she — like many kids — could benefit from some specialized tactics. Either way, the experience should be helpful.

@ Meggles: It’s so true, isn’t it, how having more than one kid can open your eyes about individual differences…and to the fact that there is no “one size fits all” approach to parenting.

I found very interested this article. Thank you for your recommendations. Actually I was a little bit worried about my 2 year old daughter. She is a very lovely kid, but shy with unknown people.Her grandma is taking care of her and she is not very often playing with kids of her age.
Just yesterday when I was stopping her on doing smth she wanted to – she started to cry, scream and act like no before. Her behavior to me was angry and aggressive. Should i be worried?

Praguesays:

April 28, 2013 at 5:18 pm

I actually find these type of articles difficult to read because I have to change the use of default male like “he” or “his” to gender neutral. When are people going to stop using sexist language?

@ Mommy Dri: I don’t think experts are worried about the occasional tantrum. That doesn’t mean you won’t, as a parent, be concerned or want to keep an eye on it. But one outburst isn’t a red flag.

@ Prague: If you read my other articles here and elsewhere, you’ll see that I alternate between “he” and “she.” I’ve written plenty of posts where the only pronoun is she. This one happened to go the other way.

I have 3 lovely children, 5, 3 and 8 months. The 2 eldest are so different from each other, my boy is very sensitif and my second girl more like me, likes the challenge, push the limits…. well at the end when it comes to bad behaviour, I ask myself: what type of outcome do I want? Usually I want me kids to be safe, to feel loved and respected. So from here I let my heart tell me what to do, and yes sometimes, time out, causing “pain” like taking away the nintendo, or something really important for them is necessary.
Always, what ever you decide to do, come back to the event and talk about it, don’t try to do it at the pic of the event ( would you like somebody giving you a moral lesson as you are in the middle of an anger burst??) but take time after so that each party gets a chance to express their feelings.
It is not easy everyday, we just try to do our best because we are mad about them.
Have an amazing day.
Christelle Donaghy
Yoga4Mothers.com

jessicasays:

April 30, 2013 at 3:05 pm

Gentle momma that’s What’s wrong with kids now days people just let their kids do whatever they want that’s why we have vaunt kids at Walmart bust their ass teach them right from wrong and I promise there wouldn’t be school shootings and bombings like we have now because they would know

Nikkisays:

April 30, 2013 at 8:11 pm

Here’s something interesting… My oldest, now 11, was very alert, happy, social, and obedient as a baby. When she grew up, however, she had major attention problems in school. She remained obedient, but began lying too and taking forever to finish tasks, such as finishing dinner and going to the bathroom. She is 11, but is the standard example of a moody, disobedient teenager. But while she possesses major attitude, one thing she does NOT display is aggression… she never has.

Now, I have a new one, and she displays some major issues. She is 11 months, and she is disobedient, hits, bites, pinches, especially if she is unhappy. I have seen other children like this and it turned out not reacting to these things and giving them plenty of stimulating and active activities to engage in helped. But I have a niece who was almost exactly like my baby and she is definitely little miss attitude and majorly disobedient and agressive at age four. It all just depends on the individual kid and how you handle the situation, I guess. I just wish I knew which way to go with my newest! It’s kind of hard to ignore her when she smacks me across the face because I tried to give her kisses.

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